A consumer watchdog has called for clearer front-of-pack labelling on takeaway pizzas after a study revealed that frozen supermarket varieties were among the healthiest.
Which? found consumers could be better off eating deep pan, stuffed crust or frozen pizzas rather than choosing the so-called "healthier" thin-based or fresh options.
Experts for the consumer group analysed 162 cheese and tomato and pepperoni pizzas available in the major supermarkets and takeaway chains, finding that frozen pizzas tended to be healthier than fresh versions.
They found thin pizzas could be higher in fat and saturates than deep pan and stuffed crust pizzas, with Tesco's Italian Romana Margherita with an "ultra thin" base containing twice as much fat and saturates per 100g as its Trattoria Verdi Deep Pan Cheese pizza.
However supermarket pizzas were not always healthier than those from takeaway chains, with Dr Oetker's Chicago Town Edge To Edge Thin And Crispy California Cheese containing more fat and saturates gram for gram than any of the cheese and tomato options, including those from Domino's and Pizza Hut.
Sainsbury's fresh Basics Cheese And Tomato Pizza had 5g of saturated fat per 100g, while Tesco's fresh Full-on-Flavour Cheese Feast Deep Crust Pizza had almost three times that amount at 14g.
Which? also found an "enormous and often unrealistic" range of portion sizes and different front-of-pack nutrition labelling schemes, even by the same manufacturer.
Goodfella's and Chicago Town were among the worst offenders for portion size, Which? said, for suggesting that consumers would eat just a quarter of a pizza.
Which? chief executive Peter Vicary-Smith said: "You can't expect people to stand poring over pizza labels in the supermarket to see which one has more fat or salt in it.
"We want clear, front-of-pack labelling, including traffic light colours, and consistent portion sizes so people can easily compare like with like."